Physiology and Health: Blood Glucose Levels and Obesity Flashcards
Chronic elevated blood glucose level leads to what?
Blood vessel damage and atherosclerosis
Chronic elevation of blood glucose level due to untreated diabetes leads to what?
Endothelial cells lining the blood vessels to take in more glucose than normal, which damages the blood vessels
Atherosclerosis may develop leading to CVD, stroke or peripheral vascular disease which affects what?
Blood vessels leading to arms, hands, legs, feet and toes
Small blood vessels that are damaged by elevated glucose levels may haemorrhage, what can this damage?
The retina, or lead to renal failure and peripheral nerve dysfunction
How is blood glucose concentration maintained within fine limits?
By negative feedback control involving the hormones insulin, glucagon and adrenaline
Blood glucose concentration is monitored by what?
Receptors in the pancreas
The pancreas controls what?
Blood glucose with the two hormones insulin and glucagon, which act antagonistically
The hormones are transported in the blood to where?
The liver
Pancreatic receptors respond to raised blood glucose level by increasing what?
The secretion of insulin from the pancreas
Insulin activates the conversion of glucose to glycogen in the liver, decreasing what?
Blood glucose concentration
Pancreatic receptors respond to lowered blood glucose level by increasing what?
The secretion of glucagon from the pancreas
Glucagon activates the conversion of glycogen to glucose in the liver increasing what?
Blood glucose concentration
During exercise and fight or flight responses, glucose concentration in the blood is raised by adrenaline, which is released from the adrenal glands, adrenaline stimulates what?
Glucagon secretion and inhibits insulin secretion
What are diabetics unable to control?
Their blood glucose concentration
What can be a chronic complication of diabetes?
Vascular disease
When does type 1 diabetes usually occur?
In childhood
What is wrong with a person with type 1 diabetes?
They are unable to produce insulin and can be treated with regular doses of insulin
When does type 2 diabetes typically develop?
Later in life
The likelihood of developing type 2 diabetes is increased by what?
Being overweight
In type 2 diabetes, individuals produce insulin but their cells are what?
Less sensitive to insulin
What is the insulin resistance linked to?
A decrease in the number of insulin receptors in the liver, leading to a failure to convert glucose to glycogen
In both types of diabetes, an individual’s blood glucose concentration rises after what?
A meal
The kidneys are unable to do what?
Reabsorb all the glucose and it appears in urine
Testing urine for glucose is often used as what?
An indicator of diabetes
What is used to diagnose diabetes?
The glucose tolerance test
Initially, the blood glucose concentration of the individual is what?
Measured after fasting
The individual then drinks a glucose solution and then what happens?
Changes in their blood glucose concentration are measured for at least the next two hours
The blood glucose concentration of a diabetic usually starts where?
At a higher level than that of a non-diabetic
During the test, a diabetic’s blood glucose concentration increases to a much higher level than that of a non-diabetic and what?
Takes longer to return to its starting concentration
Obesity can impair what?
Health
Obesity is a major risk factor for what?
Cardiovascular disease and type 2 diabetes
Obesity is characterised by what?
Excess body body fat in relation to lean body tissue such as muscle
Body mass index (BMI) is a measurement of body fat based on what?
Height and body mass
What is the equation for BMI?
BMI = body mass (kg) / height (m)²
BMI can be used to do what?
Identify people who are obese, overweight, normal or underweight
A BMI of great than 30 indicates what?
Obesity
BMI is commonly used to do what?
Measure obesity but can wrongly classify muscular individuals as obese
Obesity is linked to what?
A high-fat diet and reduced physical activity
The energy intake in the diet should do what?
Limit fats and free sugars, as fats have a high calorific value per gram and free sugars require no metabolic energy to be expended in their digestion
Exercise does what?
Increases energy expenditure and preserves lean tissue
Exercise can help to reduce risk factors for cardiovascular disease by what?
Keeping weight under control, minimising stress, reducing hypertension and improving blood lipid profiles (HDL:LDL)
